Neoarchean

Not to be confused with archaea, in spite of biological discussion commonly alluding to the only life forms of that era, e.g. microbes

The Neoarchean (pronunciation: /ˌniː.oʊ.ɑːrˈkiː.ən/; also spelled Neoarchaean) is a geologic era within the Archaean Eon.

The Neoarchean spans the period from 2,800 to 2,500 million years ago—the period being defined chronometrically and not referenced to a specific level in a rock section on Earth.

During this era, oxygenic photosynthesis first evolved, releasing an abundance of oxygen, that first reacted with minerals and afterward was free to react with greenhouse gases of the atmosphere, leaving the Earth's surface free to radiate its energy to space. This is known as the oxygen catastrophe which was to happen later in the Paleoproterozoic from a poisonous buildup of oxygen in the atmosphere, released by these oxygen producing photoautotrophs, which evolved earlier in the Neoarchean.

During this era, the supercontinent Kenorland formed at about 2,720 million years ago.

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